This is unfortunately a common situation. My main recommendation would be to call as many behavioral services in your community as possible. Specifically, I would recommend calling your local National Alliance on Mental Illness (NAMI) office. Many of the members of NAMI have dealt with similar situations. They are seasoned veterans when it comes to dealing with mentally ill family members and navigating the mental health system. They can offer you very good tips on how to handle your situation.
Another idea is calling the local community mental health center. Ask to speak with either a therapist or case manager. Other places to call include the health department, local group homes, the local emergency room/hospital (ask to speak to the hospital social worker), or the psychiatric emergency crisis center. The crisis center may be the best place to begin. Tell them about your situation and inquire whether there are any services that can assist you and your father. You might also find this information helpful as well.
“Danger to self or others” is the standard for involuntary hospitalization but there may also be a second standard referred to as “grave disability.” This means an individual could be involuntarily hospitalized if there is reason to believe that a person’s inability to care for themselves psychiatrically or medically will lead to further deterioration. Based on the description of your father’s psychiatric and physical condition he may meet the “grave disability” criteria. A psychiatric crisis team can come to the home and make a determination regarding your father’s psychiatric status.
I hope these ideas are helpful. Good luck.